The episode was eventful and finishes of the episode before it, as well as adding a new plot. I'm hoping that this episode marks the end for Mildew, or at least push him away for a while, because that plot line is getting rather tiresome now. The dragons are becoming more trusted on Berk and I doubt Mildew can do much now.
'Alvin and the Outcasts' finishes off the story introduced in the last episode and does it extremely well, with the animation in some parts being the best yet this series. My favourite episode so far, with the possible exception of the first episode.